Pitch — a complex mixture of polynuclear aromatic hydrocarbons (PAHs) - is a versatile precursor for making a variety of advanced carbon materials such as carbon fibers, carbon composites, anti-earthquake components, lubricants, battery anodes etc. Conventionally, pitches are prepared by thermal treatment of aromatic rich feedstocks. Different types of inorganic and organic catalyst are reported in the literature for promoting the polymerization and condensation reactions viz; Organic peroxides, Lewis acids (AlCl3 & FeCl3) and super acids (HF-BF3) etc. The aim of the present paper is to review and get a deeper insight into the chemistry and various mechanisms of conversion of aromatic feed stocks into petroleum base impregnating type quality pitches with or without catalyst, considering the effect of catalyst on thermal treatment, duration, reusability of catalyst and final pitch quality using lab/experimental data. The pitch prepared by above-mentioned processes compares well in properties with Ashland Petroleum Company's A-240pitch, a widely used impregnating pitch in graphite electrodes plants. These pitches also have good handling, transportation and storage properties.
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